Evaluation of shampoo.

Evaluation:

Performance characteristics:

Foam and foam stability (Ross-Miles foam column test): 200 ml of shampoo solution dropped into a glass column containing 50 ml of the same solution. The height of the foam generated is measured immediately and again after a specified time interval and considered proportional to the volume.

Detergency and cleaning action (Barnet & Powers test):Detergency depends on;

The effect of water hardness,

Surface tension and wetting

Surfactant content

Procedure: 

5 gm of sample human hair is placed at 35º C in 200 cc of water containing 1 gm of shampoo. The flask is shaken 50 times for 4 minutes and then wash, filter and dry it and weighted. The amount of soil removed under this condition can be calculated.

Wetting action (Canvas disk sinking test): 

6 canvas disk made up of mount veron cotton 1 inch in diameter is floated on the surface of the solution, and the time required to sink is measured accurately.

Rinsing: Skilled beauticians can make comparison on the performance of different shampoos.

Conditioning action: 

The degree of conditioning given to hair is ultimately judged by shampoo user who is making the evaluation on the basis of past experience and present expectation.